io_uring: add IORING_ASYNC_CANCEL_FD_FIXED cancel flag

In preparation for not having a request to pass in that carries this
state, add a separate cancelation flag that allows the caller to ask
for a fixed file for cancelation.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h
index d7ae81b..a09a78b 100644 (file)
--- a/include/uapi/linux/io_uring.h
+++ b/include/uapi/linux/io_uring.h
@@ -247,10 +247,12 @@ enum io_uring_op {
  * IORING_ASYNC_CANCEL_FD      Key off 'fd' for cancelation rather than the
  *                             request 'user_data'
  * IORING_ASYNC_CANCEL_ANY     Match any request
+ * IORING_ASYNC_CANCEL_FD_FIXED        'fd' passed in is a fixed descriptor
  */
 #define IORING_ASYNC_CANCEL_ALL        (1U << 0)
 #define IORING_ASYNC_CANCEL_FD (1U << 1)
 #define IORING_ASYNC_CANCEL_ANY        (1U << 2)
+#define IORING_ASYNC_CANCEL_FD_FIXED   (1U << 3)
 
 /*
  * send/sendmsg and recv/recvmsg flags (sqe->ioprio)

diff --git a/io_uring/cancel.c b/io_uring/cancel.c
index 500ee5f..da486de 100644 (file)
--- a/io_uring/cancel.c
+++ b/io_uring/cancel.c
@@ -24,7 +24,7 @@ struct io_cancel {
 };
 
 #define CANCEL_FLAGS   (IORING_ASYNC_CANCEL_ALL | IORING_ASYNC_CANCEL_FD | \
-                        IORING_ASYNC_CANCEL_ANY)
+                        IORING_ASYNC_CANCEL_ANY | IORING_ASYNC_CANCEL_FD_FIXED)
 
 static bool io_cancel_cb(struct io_wq_work *work, void *data)
 {
@@ -174,11 +174,14 @@ int io_async_cancel(struct io_kiocb *req, unsigned int issue_flags)
        int ret;
 
        if (cd.flags & IORING_ASYNC_CANCEL_FD) {
-               if (req->flags & REQ_F_FIXED_FILE)
+               if (req->flags & REQ_F_FIXED_FILE ||
+                   cd.flags & IORING_ASYNC_CANCEL_FD_FIXED) {
+                       req->flags |= REQ_F_FIXED_FILE;
                        req->file = io_file_get_fixed(req, cancel->fd,
                                                        issue_flags);
-               else
+               } else {
                        req->file = io_file_get_normal(req, cancel->fd);
+               }
                if (!req->file) {
                        ret = -EBADF;
                        goto done;